The endotracheal intubation treatment is sometimes required in medical practice for securing an airway of a patient having difficult airway. For example, the endotracheal intubation treatment is required in the following patients: a patient whose airway is blocked because of an accident or the like; a patient whose airway is impossible to be secured because of his/her coma state, drunkenness, or the like; a patient whose breathing has reduced or stopped because of anesthesia or the like; and a patient who needs the stent placement to his/her bronchus. The endotracheal intubation includes an oral intubation method where a tube is inserted from an oral cavity into a trachea and a nasal intubation method where a tube is inserted from a nasal cavity into a trachea.
In the conventional art of the endotracheal intubation, a stylet with a laryngoscope or a light guide is used, and for example, there is such a method that an operator introduces a tip of endotracheal tube from the inside of the laryngeal cavity to the glottis while checking visually, and then inserts the tip into the trachea.
Both of the oral intubation method and the nasal intubation method have a difficult point of endotracheal intubation. The difficult point is that it is hard to find the glottis which is an entrance of the trachea of the patient. A human body is structured in such a way that an esophagus and a trachea are diverged from each other at the vicinity of the larynx and pharynx. When the endotracheal tube is simply pushed into the trachea from the oral cavity, the endotracheal tube is generally inserted into the esophagus. The trachea is located on the chest side further than the esophagus is, and a diverging portion extending from the pharynx to the larynx is angled. The angle of the entrance of the trachea is different depending on each person. Further, the endotracheal tube has to go through various structures of a human body until reaching the trachea, such as the shape of the oral cavity, the state of the glossa, the shape of the larynx, the shape of the epiglottis, and the shape of the laryngeal cavity. Due to this, for example, in an emergency where it is necessary to secure the airway as early as possible, it is not easy to put an endotracheal tube through a trachea appropriately in short time.
As a measure for executing an endotracheal intubation most safely and reliably for a patient having a difficulty in the endotracheal intubation, there is known to be a measure of fiber-optic endotracheal intubation where an operator intubates to the trachea while seeing the area from the oral cavity to the trachea with a fiber-optic bronchoscope (hereinafter, referred to as the bronchial fiber).
The “bronchial fiber” is one kind of endoscopic instruments having 2 mm to 6 mm diameter. The bronchial fiber is inserted from the mouth or nose, introduced toward the glottis via the inside of the oral cavity or the inside of the nasal cavity while the image of the scope of the bronchial fiber is checked, and then inserted into the trachea; and thereafter, the endotracheal tube, which has been set in advance on a root portion of the fiber, is slid down by using the bronchial fiber as a guide, and inserted to and placed in the trachea (JP-A-2002-505925).
Further, as a conventional art, there is known to be a measure that, in consideration of the difficulty of the endotracheal intubation, wire is driven to the inside of the trachea from the a body surface side near the chest and drawn from an oral cavity side; and thereafter, the endotracheal tube is put into the wire to be inserted into the trachea by using the wire as a guide (JP-A-2003-235978). This measure disclosed in JP-A-2003-235978 is shown in FIGS. 20A and 20B.